Assange, 52, has been in London's high-security Belmarsh prison since 2019 and is wanted in the United States over the release of confidential U.S. military records and diplomatic cables in 2010.

"Assange is a symbol of free speech which is essential for any genuine democracy," Raggi, who ran Rome's city hall between 2016 and 2021, told Reuters.

"He has been deprived of his own liberty for years, in awful conditions, for doing his job as a journalist," she said.

Other Italian cities have taken similar steps. The northern city of Reggio Emilia granted Assange citizenship last month, while Naples is set to follow shortly.